this post was submitted on 18 Aug 2023
38 points (91.3% liked)

Programming

17402 readers
145 users here now

Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!

Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.

Hope you enjoy the instance!

Rules

Rules

  • Follow the programming.dev instance rules
  • Keep content related to programming in some way
  • If you're posting long videos try to add in some form of tldr for those who don't want to watch videos

Wormhole

Follow the wormhole through a path of communities !webdev@programming.dev



founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments

Typically the error track of the railroads analogy is implemented as a short circuit/return, so in effect this behavior IS an early return, but elegantly masked as though you are just handling the happy path.

In rust, if you function returns a Result type (the Either type from the slides), you can track a ? On to the end of any function call that returns a Result. This gets de-sugared to a check for an error and returns from the function early if it is.

At that point, the caller of the function gets to choose if they want to handle the potential failure of your function, or just let it bubble up further by using the ? operator. You end up with the behavior you’re describing, but with the benefit of errors handled by the type system and code that looks cleaner by just (explicitly) handling the happy path.